GT Limited vs. TL SHAWD 6MT

[MiniStiGuy]

the RL has a much better trans and drive system than the TL has ever gotten thus far.

 

the RDX is the closest thing to the RL's system but still lacks the electronic and mechanical control that the RL possesses. (wow that words has lots of s's)

[New Sube Dude]

downxsh1ft +1 on subies awd. [ame=http://www.youtube.com/watch?v=2OzK-oRPCbs]YouTube - Subaru Symmetrical AWD vs. Honda, Toyota, and Volkswagen[/ame] check out this link bout subaru's awd compared to other makers awd. enuf said. as far as comparing 2wd 6mt sport luxary to awd, almost all condition traction w/ turbo, to each their own. i honestly wouldnt compare the two diff. classes of vehicles...

[Verwilderd]

Subaru really fell down on that flimsy floppy new shifter didnt they?

 

That's easy to fix...and the 04-05 sti's had the same feel to them.

[HanGmaN]

what a great demo on all the manufacturers AWD systems.

 

i know all the new subaru models have Symetrical AWD, but do all models have the VDC that can do this? (ex. CVT, 5EAT, 4EAT)

 

also, is 4-motion the same as Quttro AWD?

[The B4]

what a great demo on all the manufacturers AWD systems.

 

i know all the new subaru models have Symetrical AWD, but do all models have the VDC that can do this? (ex. CVT, 5EAT, 4EAT)

 

also, is 4-motion the same as Quttro AWD?

 

all subaru models now have VDC... and 4 motion is not the same as quattro

[D0WNxSH1FT]

what a great demo on all the manufacturers AWD systems.

 

i know all the new subaru models have Symetrical AWD, but do all models have the VDC that can do this? (ex. CVT, 5EAT, 4EAT)

 

also, is 4-motion the same as Quttro AWD?

 

All Subarus have VDC now. Symmetrical AWD is different tho for each transmission.

 

Active AWD (CVT, 4EAT) = 90/10 till slip, Center Clutchpack

Continuous AWD (5MT, 6MT 2010 LGT) = 50/50 Viscous Couple Center Diff

VTD (5EAT) = 45/55 Planetary Gearset in the Center Diff

DCCD (STI) = 41/59 Planetary Gearset in Center, Helical Gear Front Diff, Torsen Rear Diff, Drive Controlled Center Diff. 50/50 lock for snow. Degress varying between.

 

4Motion is the same as Haldex Quattro AWD. (TT, A3)

4Motion is NOT the same as Torsen Quattro AWD (A4, A5, A6, A8, Q5, Q7, S's)

[The B4]

Active AWD is 90/10 until slip or until throttle, braking, and steering input says otherwise. It's constantly varying

[EJH]

downxsh1ft +1 on subies awd.

check out this link bout subaru's awd compared to other makers awd. enuf said. as far as comparing 2wd 6mt sport luxary to awd, almost all condition traction w/ turbo, to each their own. i honestly wouldnt compare the two diff. classes of vehicles...

 

That video is cool, but does the camera angle bother anyone else? Why would they shoot the video with the garage door blocking the view of the rear wheels?

[b4wantab]

Please keep in mind that if the system has a center clutch pack it can slip. The clutch packs are wet plate units and can be fully "locked" and be fully slipping without damage. Just because the clutch is locked doesn't mean the rear wheels will spin. It will have power but not enough to move the vehicle, just like that MDX with the front wheels on ice.

 

Active is a fine system and it's capable but a center diff puts an AWD system in a different league.

 

Peace,

 

Greg

[NORULZleggy]

All Subarus have VDC now. Symmetrical AWD is different tho for each transmission.

 

Active AWD (CVT, 4EAT) = 90/10 till slip, Center Clutchpack

Continuous AWD (5MT, 6MT 2010 LGT) = 50/50 Viscous Couple Center Diff

VTD (5EAT) = 45/55 Planetary Gearset in the Center Diff

DCCD (STI) = 41/59 Planetary Gearset in Center, Helical Gear Front Diff, Torsen Rear Diff, Drive Controlled Center Diff. 50/50 lock for snow. Degress varying between.S's)

 

 

So I know my 2.5I is not CVT, so which 2.5I's have the 90/10 split? i am just stumped and want more info, i mean i am going to test it out in the snow for sure. hehe

[D0WNxSH1FT]

So I know my 2.5I is not CVT, so which 2.5I's have the 90/10 split? i am just stumped and want more info, i mean i am going to test it out in the snow for sure. hehe

 

CVT and 4EAT. The only 2.5i w/o 90/10 Active AWD are MANUAL.

[Verwilderd]

^What he said...

 

Every 4eat/cvt have active (90/10). Manuals are 50/50 continuous and the rest of the cars are variable torque (45/55)....only with the sti you have the dccd that allows the individual to move the torque around and lock it.

[NORULZleggy]

Ok cool so it's 90/10. would it be able to go 60/40 if needed?

[b4wantab]

Yes, it can go from 90/10 to 50/50. It can't go 49/51 or any sort of rear wheel bias. It also can't regulate side to side on the front or the rear.

 

Keep in mind that older 4EATs had a center diff and VTD. They can go rear wheel bias.

 

Peace,

 

Greg

[Beanboy]

Also remember that any of these Subarus theoretically can have near 100% of engine torque measured at either set of wheels (one set off ground, other on dyno) depending on how well the limited slip/clutch plates hold.

 

Don't think anybody has measured it, but the viscous limited slip is probably gonna ooze a good 10%-15% of the torque whereas the STI probably can get near 100%, with the system in the autos somewhere in-between.

[NORULZleggy]

Thank you all for the insight, I do understand now. It's like the test vid I saw in the rain on slick pavement. the punched it in a 4WD car and the back wheels were going on and off like a light. In the legacy the car took off fine on the slick rain pavement. wooottt AWD in subies rock ahahahhaah

[D0WNxSH1FT]

Hahha yes, Subaru, Audi and the Evo have the best systems.

[Verwilderd]

Hahha yes, Subaru has the best systems.

corrected

[05GT Guru]

Never liked the Evo AWD because its still uses a transfer case thanks to the horizontal engine

[Sideways the Seven]

The new Saab XWD system is pretty awesome too. A similar system is supposed to be coming in the new Golf R too. http://en.wikipedia.org/wiki/Saab_XWD

Fourth generation - 2007

Saab introduces a unique combination of Haldex Couplings on its 9-3 Turbo-X in late 2007. Called XWD (Cross-Wheel Drive), it allows enhanced traction, safer driving, and better control.[6] The main components of the new Haldex system are the Power Take-Off Unit (PTU), Limited Slip Coupling (LSC) and eLSD (Electronic Limited Slip Differential). The PTU is the final drive unit at the front of the vehicle that transmits power to the front wheels and sends power down the driveshaft to the rear wheels. It is not a Haldex design, but is required to adapt the system to a front-wheel drive vehicle. The LSC sits at the rear of the vehicle in-line with the driveshaft. It controls the torque split between the front and rear wheels of the vehicle. The LSC sends torque to the eLSD that sits between the rear wheels. The eLSD transfers torque to the two rear wheels. Like with XWD, previous generation Haldex systems also included an LSC and an LSD. However, with the new system Haldex significantly redesigned the workings of their LSC. The LSC is still a clutch pack that adjusts torque split depending on hydraulic pressure. It is the method of fluid flow through the device that has changed.

A large complaint about the old system was its lagging response time. LSC versions 3.0 and earlier used a built-in pump to create hydraulic pressure on the clutch pack to increase the torque drive to the rear wheels. While efforts were made on Haldex's part to create pre-emptive torque by adding a check valve and feeder pump to provide some instant pressure when triggered by wheel slippage, it was still limited in capacity. That is why for version 4.0 Haldex made an effort to improve response time by eliminating the hydraulic pump built in to the LSC, which also reduced its overall packaging size. Instead they have added a proportional pressure release valve with an accumulator that is kept filled by a detached feeder pump. This provides more instant response by holding the valve open to limit the torque drive to the rear wheels and keeping the hydraulic fluid flowing through the system. That way when rear torque is demanded, the valve closes and hydraulic pressure is already there.

The LSD used by Haldex 4.0 is also not the mechanical limited-slip differential of old. They swapped the old system LSD for an electronic unit. The eLSD works in much the same way as the LSC, a feeder pump and pressure relief valve are used to control hydraulic pressure on the differential clutch pack. This allows for complete control of the rear differential lock-up without the need to wait for wheel slippage to occur. The system has its own control unit contained in the LSC. This control unit communicates between the vehicle systems to get sensor input for data such as wheel speed, rpms, throttle position, steering wheel input, etc. It also works with anti-lock brake and traction control systems.

The XWD system can transmit 100 percent of available torque to either the front or rear wheels. However, for those conditions to occur one end of the vehicle would have to lose all traction, like driving on ice for instance. During a standing start the rear wheels are put to use, without the need for any slip to occur. Then under straight-line cruising conditions, to conserve fuel and driveline wear, the torque split to the rear wheels is reduced to a level between 5 and 10 percent. Also up to 85 percent of torque can be transferred by the eLSD between to any single rear wheel if necessary. The system can adjust torque splits based on calculated conditions, such as those that indicate an aggressive lane change manoeuvre, to effectively reduce overstreer or understeer without any wheel slip occurring. In the event that some wheel slip does actually get to occur, the system can react more timely and efficiently than in the past. [7]

Thanks to this technology, the Saab 9-3 Turbo-X, with only 280 bhp (210 kW) can run a slalom faster than many high performance sports cars, beating German and Japanese rivals, including the Porsche 911 Turbo. Saab has an agreement with Haldex for exclusive first year access to the technology. Haldex is currently developing a XWD system for Hyundai Applications.

[Verwilderd]

It's still not symmetrical.

[D0WNxSH1FT]

The new Saab XWD system is pretty awesome too. A similar system is supposed to be coming in the new Golf R too.

 

Those are merely Haldex-4 system which is FWD-biased until slip (90/10) based system w/ the ability to send (30/70 max) 70% torque to either rear wheel. It is identical to the cheapo-SH-AWD. They are reactive systems and have nothing on the proactive Continuous, VTD or DCCD subaru systems. Also, that 70% to the rear is determined by RPM. So if you are driving slow or cruising on the Highway (high gear, low RPM) you won't get anywhere near 70%.

 

Only the Evo X's S-AWC and Audi's Sport Differential (2010 S4) can send and distribute power regardless of RPM (even in neutral) to each rear tire.

[Sideways the Seven]

It's still not symmetrical.

 

Oh, I know, I was just stating that it's a pretty good system.

 

Those are merely Haldex-4 system which is FWD-biased until slip (90/10) based system w/ the ability to send (30/70 max) 70% torque to either rear wheel. It is identical to the cheapo-SH-AWD. They are reactive systems and have nothing on the proactive Continuous, VTD or DCCD subaru systems. Also, that 70% to the rear is determined by RPM. So if you are driving slow or cruising on the Highway (high gear, low RPM) you won't get anywhere near 70%.

 

Only the Evo X's S-AWC and Audi's Sport Differential (2010 S4) can send and distribute power regardless of RPM (even in neutral) to each rear tire.

 

While you're right about the torque split, my point was that it's a reactive system, but reacts so fast (MUCH faster than either SH-AWD car I drove) that it almost seems proactive and it is one of the better systems out there. If you're fortunate enough to have a dealership in your area with a Saab Turbo X on the lot, you should take it for a test drive. Make sure to sneak in a hard launch.

 

*note*

Before someone misunderstands my post, I am not saying that this is superior to Subaru or Audi's setups, I just wanted to throw it out there.

[camber]

Please keep in mind that if the system has a center clutch pack it can slip. The clutch packs are wet plate units and can be fully "locked" and be fully slipping without damage. Just because the clutch is locked doesn't mean the rear wheels will spin. It will have power but not enough to move the vehicle, just like that MDX with the front wheels on ice.

 

Active is a fine system and it's capable but a center diff puts an AWD system in a different league.

 

Peace,

 

Greg

 

El cheapo SH-AWD doesn't have a center clutch pack but neither does the RL version. However, you could say the bit is just trasferred to the rear differential. The clutch packs in el cheapo AWD is not wet. It's three dry paper plate clutches. One for drive shaft, the other two for rear drive axles. The El cheapo version of SH-"AWD" is a really poor(and much cheaper way) of pulling off "torque vectoring" aspect of SH-AWD. It's now where near as capable as the RL AWD system.

[05subiegt]

I drive a 2005 Legacy GT and I'll be the first to admit that it can't handle worth shit. But I still chose it because practically everything about it appealed to me, and it is still a blast to drive. If I had the choice between it and the 2005 TL I would take the TL in a second. Better interior, faster in a straight line, better on gas. I'm sure it could handle better too. I think these generations of the Legacy and TL were the best looking, IMO their designers took it over the top with the latest generations. I don't know much about SH-AWD but I'm confident to say it's a better system than Subaru all wheel drive.